package com.wxhandle.cleandemo.api.security;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpMethod;
import org.springframework.security.access.SecurityMetadataSource;
import org.springframework.security.access.intercept.AbstractSecurityInterceptor;
import org.springframework.security.access.intercept.InterceptorStatusToken;
import org.springframework.security.web.FilterInvocation;
import org.springframework.security.web.access.intercept.FilterInvocationSecurityMetadataSource;

// @Slf4j
public class DefaultFilterSecurityInterceptor extends AbstractSecurityInterceptor implements Filter  {
    
    private FilterInvocationSecurityMetadataSource securityMetadataSource;

    //注入
    @Autowired
    public void setDefaultAccessDecisionManager(DefaultAccessDecisionManager accessDecisionManager) {
        super.setAccessDecisionManager(accessDecisionManager);
    }
    
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        FilterInvocation fi = new FilterInvocation(request, response, chain);
        //OPTIONS请求直接放行
        if(httpRequest.getMethod().equals(HttpMethod.OPTIONS.toString())){
            fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
            return;
        }
        invoke(fi);
    }

    private void invoke(FilterInvocation fi) throws IOException, ServletException {
        //fi里面有一个被拦截的url
        //里面调用MyInvocationSecurityMetadataSource的getAttributes(Object object)这个方法获取fi对应的所有权限
        //再调用MyAccessDecisionManager的decide方法来校验用户的权限是否足够
        InterceptorStatusToken token = super.beforeInvocation(fi);
        try {
            //执行下一个拦截器
            fi.getChain().doFilter(fi.getRequest(), fi.getResponse());
        } finally {
            super.afterInvocation(token, null);
        }
    }

    @Override
    public Class<?> getSecureObjectClass() {
        return FilterInvocation.class;
    }

    @Override 
    public SecurityMetadataSource obtainSecurityMetadataSource() {
        return this.securityMetadataSource;
    }

    
    public FilterInvocationSecurityMetadataSource getSecurityMetadataSource() {
        return this.securityMetadataSource;
    }

    //设置自定义的FilterInvocationSecurityMetadataSource
    @Autowired
    public void setSecurityMetadataSource(DefaultInvocationSecurityMetadataSource messageSource) {
        this.securityMetadataSource = messageSource;
    }

	public void setAccessDecisionManager(DefaultAccessDecisionManager accessDecisionManager) {
        super.setAccessDecisionManager(accessDecisionManager);
	}
}
